Vetta 2 No Sound.....

Hi, Im Lloyd and im new here. I got a used vetta2 hd online from guitar center and just got it hooked up a bit ago and I cant get any sound. Im new to this thing and have tried to look at the manual but have found no fix yet. I have no clue what I am doing!!

Im not sure if the damn thing works or not. When I plug it into my cab in mono, it makes noise from the speakers, the same noise over and over. When I plug it up stereo the noise goes away but theres no sound. The tuner works when I have my guitar plugged in but just no sound accept for when I have it plugged in mono and it just makes the noise.

I have the vetta plugged into a marshall 1960A and I know it works and that theres no problems with the cab. I just want to make sure its not my fault the amps not working before I box it up and ship it back. I cant even figure out how to do a factory reset on the thing. Im new to the Line6 gear and maybe its just to much?